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61.
Studies on the mechanism of bacterial resistance to complement-mediated killing. II. C8 and C9 release C5b67 from the surface of salmonella minnesota S218 because the terminal complex does not insert into the bacterial outer membrane 总被引:22,自引:2,他引:22
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The mechanism for consumption of terminal complement components and release of bound components from the surface of serum-resistant salmonella minnesota S218 was studied. Consumption of C8 and C9 by S218 occurred through interaction with C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8-deficient serum and washed to remove all C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8- deficient serum and washed to remove al but cell bound C5b67. Rapid release of (125)I C5 and (125)I C7 from the membrane of S218 was dependent on binding of C8 because (125)I C5 and (125)I C7 deposition in C8D serum was stable and was twofold higher in C8D than in PNHA, and addition of purified C8 or C8 and C9 to S218 previously incubated in C8D serum caused rapid release of (125)I C5 and (125)I C7 from the organism. Analysis by sucrose density gradient ultracentrifugation of the fluid phase from the reaction of S218 and 10 percent PNHS revealed a peak consistent with SC5b-9, in which the C9:C7 ratio was 3.3:1, but the NaDOC extracted bound C5b-9 complex sedimented as a broad peak with C9:C7 of less than 1.2:1. Progressive elution of C5b67 and C5b-9 from S218 but not serum-sensitive S. minnesota Re595 was observed with incubation in buffers of increasing ionic strength. Greater than 90 percent of the bound counts of (125)I C5 or (125)I C9 were released from S218 by incubation in 0.1 percent trypsin, but only 57 percent of (125)I C9 were released by treatment of Re595 with trypsin. These results are consistent with the concept that C5b-9 forms on the surface of the serum-sensitive S. minnesota S218 in normal human serum, but the formed complex is released and is not bactericidal for S218 because it fails to insert into hydrophobic outer membrane domains. 相似文献
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幽门螺杆菌感染处理的当前观念——MaastrichtⅢ共识报告 总被引:8,自引:0,他引:8
P Malfertheiner F Megraud C O'Morain F Bazzoli E El-Omar D Graham R Hunt T Rokkas N Vakil EJ Kuipers 朱琦 《胃肠病学》2007,12(3):159-169
名词缩写
欧洲幽门螺杆菌研究小组:European Helicobacter Study Group,EHSG
胃食管反流病:gastro-esophageal reflux disease,GERD 相似文献
65.
Background
In November 2006, an email-based health promotion program for pregnant women was implemented nationally in the Netherlands. The program consisted of emails containing quizzes with pregnancy-related questions tailored to the number of weeks of pregnancy. Emails were sent out once every 4 weeks, up to a maximum of nine emails.Objectives
The aims of the study were (1) to assess the recruitment of participants and their representativeness of the Dutch population and (2) to study differences in recruitment, program use, and program appreciation among women with different levels of education.Methods
Data from 13,946 pregnant women who enrolled during the first year of the program were included. Upon registration, participants were asked how they found out about the program and subsequently received an email questionnaire to assess demographic, lifestyle, and Internet characteristics. Program use was tracked, and participants were classified into five user groups (inactive to very active). Program appreciation (low, intermediate, and high) was assessed twice with an email questionnaire that was sent after the woman had received her third and sixth quiz email. Information about pregnant women and their characteristics was obtained from Dutch registries to assess representativeness of the study population.Results
About 8% of the pregnant women in the Netherlands enrolled in the program. Immigrants were underrepresented, and women with a low level of education seemed to be slightly underrepresented. Most women knew about the program from a promotional email sent by the organization (32%), followed by the Internet (22%) and midwives (16%). Women with little education were more often inactive users of the program than were highly educated women (15% vs 11%, P < .001), whereas highly educated women were more often very active users compared with women with little education (25% vs 20%, P< .001). However, women with less education were more likely than women with more education to have a high appreciation of the program after receiving three quiz emails (52% vs 44%, P = .001).Conclusions
In this real-life setting, pregnant women can be reached through an email-based health promotion program. Selective engagement by education level remains a challenge. 相似文献66.
Boren SA Gunlock TL Schaefer J Albright A 《The Diabetes educator》2007,33(6):1053-77; discussion 1078-9
OBJECTIVE: The purpose of this systematic review was to review published literature on risk-reducing interventions as part of diabetes self-management. DATA SOURCES: Medline (1990-2007), CINAHL (1990-2007), and Cochrane Central Register of Controlled Trials (first quarter 2007) databases were searched. Reference lists from included studies were reviewed to identify additional studies. STUDY SELECTION: Intervention studies that addressed reducing risks to help prevent or minimize diabetes complications were included. DATA EXTRACTION: Study design, sample characteristics, interventions, and outcomes were extracted. DATA SYNTHESIS: Thirty-three studies, represented by 39 articles, met the criteria for inclusion and were classified as smoking cessation (n = 3), eye examination (n = 2), foot care (n = 10), oral health (n = 2), vaccination (n = 1), cardiovascular risk reduction (n = 9), and comprehensive risk reduction (n = 6). Only 46.3% of the 283 outcomes measured in the 33 studies were significantly improved. CONCLUSIONS: Reducing risks involves implementing effective risk reduction behaviors to prevent or slow the progression of diabetes complications. Recognizing risk factors for complications and what constitutes optimal preventive care is an important part of managing diabetes. Intervention studies are lacking in some areas of reducing risks. Further studies are needed to test specific interventions to reduce the risks of diabetes complications. 相似文献
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LP Queiroz MFP Peres EJ Piovesan F Kowacs MC Ciciarelli JA Souza & E Zukerman 《Cephalalgia : an international journal of headache》2009,29(6):642-649
The aim of this study was to estimate the 1-year prevalence of migraine and the degree of the association of migraine with some sociodemographic characteristics of a representative sample of the adult population of Brazil. This was a cross-sectional, population-based study. Telephone interviews were conducted on 3848 people, aged 18–79 years, randomly selected from the 27 States of Brazil. The estimated 1-year gender- and age-adjusted prevalence of migraine was 15.2%. Migraine was 2.2 times more prevalent in women, 1.5 times more in subjects with > 11 years of education, 1.59 times more in subjects with income of < 5 Brazilian Minimum Wages per month, and 1.43 times more in those who do not do any physical exercise. The overall prevalence of migraine in Brazil is 15.2%. Migraine is significantly more prevalent in women, subjects with higher education, with lower income, and those who do not exercise regularly, independently of their body mass index. 相似文献
69.
Visual identification of bacterially contaminated red cells 总被引:1,自引:0,他引:1
There have been increasing numbers of reports of transfusion-acquired Yersinia enterocolitica bacteremia (including several fatal cases). Fifteen units of whole blood were inoculated with various concentrations of Y. enterocolitica serotype 0:3 and processed into AS-3 preserved red cells (RBCs). Consistent growth of the organism was found at inoculum concentrations greater than or equal to 10 colony-forming units per mL. In all 13 units of RBCs that supported the growth of Y. enterocolitica, a darkening in color (due to hemolysis and a decrease in pO2) was observed in the bag. The attached sample segments, which were sealed from the main unit, remained sterile and did not darken. This color change was apparent in all the contaminated units by Day 35, which was 1.5 to 2 weeks after the bacteria were first detected in cultures of the blood. Hence, by comparison of the color of the segment tubing with that of the unit itself, units grossly contaminated with Y. enterocolitica can be identified prior to transfusion. Moreover, review of photographs on file at the Centers for Disease Control revealed this dramatic color change in 2 units of blood that caused transfusion-transmitted sepsis (Enterobacter agglomerans and an unidentified gram-negative bacillus, not Yersinia sp.), which demonstrated that the color change was not limited to Y. enterocolitica. This method of visual identification of contaminated units of blood could decrease the incidence of posttransfusion bacterial sepsis. 相似文献
70.